1. Field of the Invention
This invention relates to foundry practice, and more particularly to faced metal mould automatic casting lines and is directly concerned with apparatus for cleaning faced metal moulds of used facing.
2. Description of the Prior Art
It is known that faced metal moulds are successfully used for producing quality castings of practically any configuration from various metals, inclusive of cast iron with flaked and spheroidal graphite, carbon and alloyed steel and other metals and alloys, the geometric dimensions ranging from a few dozens of millimeters to one meter and more, and from a few hundred grams to 300 and over kilograms.
It is advantageous to use faced metal moulds for casting of crankshaft for automobile and tractor (inclusive of diesel) engines, camshafts for automobile engines, ribbed frames for electric motors, railway car roller bearing boxes, hydraulic distributor housings with cast conduits, tractor drive sprockets and miscellaneous other items.
An indispensible process operation in faced metal mould casting is the removal, upon demoulding, of used facing from the faced portions of the metal mould. It is necessary to remove both the burnt and partly damaged facing that has come into contact with molten metal and the unburnt facing that has not contacted molten metal.
The quality of cleaning governs that of the fresh facing applied to the faced parts of the metal mould, and thus the quality of castings.
There is known an apparatus for cleaning faced metal mould parts of used facing (see, e.g., R. L. Snezhnoi et al, "Tekhnologicheskiye osnovy i kompleksnaya mekhanizatsiya protsesov polucheniya otlivok iz chernykh splavov v oblitsovannykh kokilyakh"/Process Fundamentals and Complex Mechanization of the Manufacture of Castings from Iron Alloys in Faced Metal Moulds/, "Liteinoye proizvodstvo", 1973, No. 11.
The apparatus referred to above is mounted on a conveying roller table whereon are transferred, working face up, parts of metal moulds to be cleaned of used facing. The apparatus comprises a frame whereupon in pivotally mounted a traverse accommodating a plate provided with a set of working tools for breaking up the facing and with a set of blowing nozzles connected to a system for supplying a working agent such as compressed air intended for removing the burnt and the chipped off facing.
The working tools are formed with sharp-edged rollers carried by spring-loaded oscillating levers. As the parts of the metal mould pass underneath said apparatus, the rollers are forced against the metal mould surface to break up (chip off) the facing in the parting plane.
The apparatus is capable of removing used facing from those parts of metal moulds which have no projections above the parting plane, this greatly restricting the field of application thereof. The apparatus fails to clean those parts of metal moulds having internal cavities whose facing never comes into contact with molten metal, e.g., core seats, etc.
Thus, the use of a single conveyor handling both the top and the bottom metal mould parts, of which at least one has elements protruding above the parting plane, renders such apparatus altogether impractical. The apparatus of this type is also unfit for use where two different kinds of metal moulds are employed in a single production line, which is frequently the case in modern faced metal mould casting lines, with at least one of its parts protruding above the parting plane.